Mechanisms of creep deformation in polycrystalline Ni-base disk superalloys

Unocic, RR and Viswanathan, GB and Sarosi, PM and Karthikeyan, S and Li, J and Mills, MJ (2008) Mechanisms of creep deformation in polycrystalline Ni-base disk superalloys. In: Materials Science and Engineering: A, 483-48 . pp. 25-32.

Preview

PDF 2008_MSE-A_V483_pp25-32.pdf Download (952kB)

Abstract

This paper reviews the presently proposed mechanisms for creep of {\gamma^{\prime}} strengthened Ni-base superalloys that are typically used for disk applications. Distinct creep strength controlling modes, such as dislocation-coupled antiphase-boundary shearing, shearing configurations involving superlattice stacking faults, Orowan looping, climb by-pass, and microtwinning have been observed. These are strongly influenced by the scale of the {\gamma^{\prime}} precipitating phase and are operative within specific ranges of temperature and stress. Insight from more recent experimental findings concerning microtwinning and extending stacking fault mechanisms suggest important similarities between these deformation modes. It is suggested that local atomic reordering in the wake of Shockley partials is responsible for the temperature dependence exhibited in this regime.

Item Type:	Journal Article
Publication:	Materials Science and Engineering: A
Publisher:	Elsevier
Additional Information:	Copyright of this article belongs to the Elsevier
Keywords:	Creep;Deformation mechanisms;Ni-base superalloy;Microtwinning
Department/Centre:	Division of Mechanical Sciences > Mechanical Engineering
Date Deposited:	19 Jun 2008
Last Modified:	19 Sep 2010 04:46
URI:	http://eprints.iisc.ac.in/id/eprint/14368

Actions (login required)

View Item